Earthworms. They seem harmless enough, right? You usually run into them on the sidewalk after it rains or when you’re weeding your garden. What if I told you that earthworms are actually not native to many parts of the United States (specifically, the northern Great Lakes region), and were probably brought there by European settlers in the 1800s? Earthworms are really NOT the simple little creatures that they appear to be–and they sure can wreak havoc a non-native habitat!

Aren’t worms supposed to be good for the earth? Well, yes, when they are naturally-occurring. Exotic earthworms can lead to plant decomposition, changes in soil structure, and reduction in nutrient availability. These ground-level forest ecosystem shifts can lead to a chain reaction, affecting many other wildlife and plant species, and opening the door to other exotic species to invade. And simply saying “earthworms” isn’t really accurate-there are actually many thousand varieties of earthworms, and at least 16 are known to have invaded the Great Lakes region. Worms don’t seem so simple anymore, eh?

Luckily, Great Lakes Worm Watch, headquartered at the University of Minnesota, is on the case, and offering many opportunities to get involved, even if you’re not located in the Great Lakes region. According to their mission statement:

We provide the tools and resources for citizens to actively contribute to the development of a database documenting the distributions of exotic earthworms and their impacts across the region as well as training and resources for educators to help build understanding of the methods and results of scientific research about exotic earthworms and forest ecosystems ecology.

While new information is always emerging about exotic earthworm invasions and how they affect ecosystems, very little data exists about earthworm distribution across the Great Lakes region. While this information is invaluable to scientists studying these trends, it’s labor-intensive and expensive to fund, so volunteers are critical to this organization! The “How can I join?” section of the Worm Watch site outlines many ways that interested citizen scientists can get involved in ongoing earthworm studies and even start their own! There are also ideas for how we can help “stop the spread,” through simple adjustments to how you garden, bait fish, etc. The site is also a fantastic resource for educators, including ideas for games and activities to use in the classroom.

If you’re interested in more information about the Great Lakes Worm Watch, or have questions about getting involved, you can contact Ryan Hueffmeier at the Natural Resources Research Institute at UM-Duluth, at greatlakeswormwatch@gmail.com.

As any gardener will tell you, earthworms are good for your garden. However, that same ability to compost organic material into rich, black soil in your backyard may actually be having a detrimental impact on some forests, and in turn, carbon storage.

Earthworms, you see, are not native to the province of Alberta in Canada. Indeed, apparently most of Canada’s native earthworms died out during the last ice age; the worms you see today are likely invasive species that somehow made their way across the ocean with European immigrants. Earthworms eat will eat copious amounts of leaf litter on the forest floor, and this speeds up soil decomposition. It’s not yet clear how this affects the growth cycles of trees, forest plants, and the birds, mammals and invertebrates that live in forests where worms have not been found before.

So how does climate change come into it? Leaf litter, as it accumulates in forest soil, works like a carbon dioxide bank, storing it underground. So scientists now want to know if earthworms reduce carbon storage, and if so by how much? Initial research by Dr. Erin Cameron suggests that it might be as much as a 37% decrease; this could have a significant impact on climate change.

Given this data, the Alberta Worm Invasion Project has a mandate to slow the spread of earthworms in Alberta. As you might suspect, human activity is still a major cause of accelerated earthworm spread, as worm eggs can cling to car tires, and fishers tend to dump their bait at the end of a day out fishing. The project has a public awareness campaign going to help reduce the impact of human activity.

On the citizen science side, the Worm Invasion Project wants your help to track the spread of earthworms in Alberta. The Worm Tracker is an iOS app that allows you to track where and when you find earthworms in the province. There’s a field guide to help you identify species, and you can use Google Earth to explore some of the data.